US6787079B2 - Method for making a multi-layer expanded shoe sole - Google Patents
Method for making a multi-layer expanded shoe sole Download PDFInfo
- Publication number
- US6787079B2 US6787079B2 US10/213,869 US21386902A US6787079B2 US 6787079 B2 US6787079 B2 US 6787079B2 US 21386902 A US21386902 A US 21386902A US 6787079 B2 US6787079 B2 US 6787079B2
- Authority
- US
- United States
- Prior art keywords
- unexpanded
- blank
- molding
- unexpanded blank
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related, expires
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D35/00—Producing footwear
- B29D35/12—Producing parts thereof, e.g. soles, heels, uppers, by a moulding technique
- B29D35/14—Multilayered parts
- B29D35/142—Soles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/02—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles
- B29C44/08—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles using several expanding or moulding steps
- B29C44/083—Increasing the size of the cavity after a first part has foamed, e.g. substituting one mould part with another
- B29C44/086—Increasing the size of the cavity after a first part has foamed, e.g. substituting one mould part with another and feeding more material into the enlarged cavity
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/34—Auxiliary operations
- B29C44/3484—Stopping the foaming reaction until the material is heated or re-heated
Definitions
- This invention relates to a method for making a multi-layer expanded shoe sole, more particularly to a method for making a multi-layer expanded shoe sole with a clear-cut boundary between two adjacent sole layers of the expanded shoe sole.
- a multi-layer shoe sole may be prepared by a conventional method involving the step of stacking and thermal molding hardened unexpanded blanks in a mold to permit the unexpanded blanks to undergo a reaction for cross-linking and expansion.
- the aforesaid method is disadvantageous in that adjacent hardened unexpanded blanks are required to have shapes which would substantially fit to each other in order to form the shoe sole with a clear-cut boundary between two adjacent sole layers of the shoe sole.
- arrangement and positioning of the adjacent hardened unexpanded blanks in the mold is inconvenient.
- the bonding strength between the adjacent sole layers of the shoe sole tends to be relatively poor, and gaps may be formed between the adjacent sole layers of the shoe sole.
- the object of the present invention is to provide a method for making a multi-layer expanded shoe sole that is capable of overcoming the aforementioned drawbacks.
- a method for making a multi-layer expanded shoe sole comprises the steps of: (a) molding a first foamable material to form a first unexpanded blank, and cooling the first unexpanded blank to a low temperature to harden the first unexpanded blank; (b) molding a second foamable material to form a second unexpanded blank, and maintaining the second unexpanded blank at a high temperature such that the second unexpanded blank is in a softened state; and (c) stacking and thermal molding the first and second unexpanded blanks in a mold at a molding temperature to permit the first and second unexpanded blanks to undergo a reaction for cross-linking and expansion.
- FIG. 1 is a flow diagram illustrating consecutive steps of a method embodying this invention for making a multi-layer expanded shoe sole
- FIG. 2 is a sectional view to illustrate how the first and second unexpanded blanks are placed in a mold according to the method of this invention
- FIGS. 3 and 4 are sectional views to illustrate how the first and second unexpanded blanks are thermally pressed by the mold according to the method of this invention.
- FIGS. 5 and 6 are sectional views of unfinished and finished multi-layer expanded shoe soles formed according to the method of this invention.
- FIG. 1 shows consecutive steps of a method embodying this invention for making a multi-layer expanded shoe sole that includes an outer sole layer 110 and an inner sole layer 120 surrounded by the outer sole layer 110 (see FIGS. 5 and 6 ).
- the method includes the steps of: (a) molding a first foamable material to form a first unexpanded blank 10 , and cooling the first unexpanded blank 10 to a low temperature to harden the first unexpanded blank 10 ; (b) molding a second foamable material to form a second unexpanded blank 20 , and maintaining the second unexpanded blank 20 at a high temperature such that the second unexpanded blank 20 is in a softened state; and (c) stacking and thermal molding the first and second unexpanded blanks 10 , 20 in a mold 200 (see FIGS.
- the mold 200 includes complementary female and male mold halves 210 , 220 .
- the first and second foamable materials are preferably made from a molding composition that contains ethylene-vinyl acetate copolymer (EVA).
- EVA ethylene-vinyl acetate copolymer
- the low temperature for the first unexpanded blank 10 is preferably set in a range of from room temperature to 50° C.
- the high temperature for the second unexpanded blank 20 is preferably set in a range of from 70 to 110° C.
- the molding temperature for the mold 200 is preferably set in a range of from 150 to 180° C.
- the first unexpanded blank 10 has a peripheral wall 11 with a U-shaped cross-section that conforms to an inner wall 212 of the female mold half 210 of the mold 200 .
- the second unexpanded blank 20 has a height greater than and a cross-section smaller than those of a recess 12 defined by the peripheral wall 11 of the first unexpanded blank 10 , thus facilitating placement of the second unexpanded blank 20 in the recess 12 .
- the aforesaid cross-section lies in a plane transverse to the height of the second unexpanded blank 20 .
- first unexpanded blank 10 is in a hardened state prior to the reaction, the shape thereof remains substantially the same during the aforesaid reaction, and since the second unexpanded blank 20 is in a softened state prior to the aforesaid reaction, shape of the second unexpanded blank 20 can be made to conform to the shape of the recess 12 in the first unexpanded blank 10 during the reaction, and a clear-cut boundary between the outer and inner sole layers 110 , 120 can be achieved, thereby eliminating the aforesaid drawback as encountered in the prior art.
- the first unexpanded blank 10 is formed with a flange 13 that radially and outwardly extends from a top end of the peripheral wall 11 and that is seated on an upper surface 211 of the female mold half 210 adjacent to a groove 213 formed in the upper surface 211 of the female mold half 210 so as to enhance sealing effect between the female and male mold halves 210 , 220 during the aforesaid reaction.
- the flange 13 of the first unexpanded blank 10 results in a flange 130 of the outer sole layer 110 in the groove 213 (see FIGS. 4 and 5 ).
- the flange 130 is subsequently trimmed from the outer sole layer 110 to form the final product of the shoe sole of this invention (see FIG. 6 ).
- the male mold half 220 is formed with a groove 223 so as to permit forming of a flange 140 on a top end of the inner sole layer 120 .
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Footwear And Its Accessory, Manufacturing Method And Apparatuses (AREA)
Abstract
A method for making a multi-layer expanded shoe sole includes the steps of (a) molding a first foamable material to form a first unexpanded blank and cooling the first unexpanded blank to a low temperature to harden the first unexpanded blank, (b) molding a second foamable material to form a second unexpanded blank and maintaining the second unexpanded blank at a high temperature such that the second unexpanded blank is in a softened state, and (c) stacking and thermal molding the first and second unexpanded blanks in a mold at a molding temperature to permit the first and second unexpanded blanks to undergo a reaction for cross-linking and expansion.
Description
1. Field of the Invention
This invention relates to a method for making a multi-layer expanded shoe sole, more particularly to a method for making a multi-layer expanded shoe sole with a clear-cut boundary between two adjacent sole layers of the expanded shoe sole.
2. Description of the Related Art
A multi-layer shoe sole may be prepared by a conventional method involving the step of stacking and thermal molding hardened unexpanded blanks in a mold to permit the unexpanded blanks to undergo a reaction for cross-linking and expansion. However, the aforesaid method is disadvantageous in that adjacent hardened unexpanded blanks are required to have shapes which would substantially fit to each other in order to form the shoe sole with a clear-cut boundary between two adjacent sole layers of the shoe sole. As a consequence, arrangement and positioning of the adjacent hardened unexpanded blanks in the mold is inconvenient. Moreover, the bonding strength between the adjacent sole layers of the shoe sole tends to be relatively poor, and gaps may be formed between the adjacent sole layers of the shoe sole.
Therefore, the object of the present invention is to provide a method for making a multi-layer expanded shoe sole that is capable of overcoming the aforementioned drawbacks.
According to the present invention, a method for making a multi-layer expanded shoe sole comprises the steps of: (a) molding a first foamable material to form a first unexpanded blank, and cooling the first unexpanded blank to a low temperature to harden the first unexpanded blank; (b) molding a second foamable material to form a second unexpanded blank, and maintaining the second unexpanded blank at a high temperature such that the second unexpanded blank is in a softened state; and (c) stacking and thermal molding the first and second unexpanded blanks in a mold at a molding temperature to permit the first and second unexpanded blanks to undergo a reaction for cross-linking and expansion.
In the drawings which illustrate an embodiment of the invention,
FIG. 1 is a flow diagram illustrating consecutive steps of a method embodying this invention for making a multi-layer expanded shoe sole;
FIG. 2 is a sectional view to illustrate how the first and second unexpanded blanks are placed in a mold according to the method of this invention;
FIGS. 3 and 4 are sectional views to illustrate how the first and second unexpanded blanks are thermally pressed by the mold according to the method of this invention; and
FIGS. 5 and 6 are sectional views of unfinished and finished multi-layer expanded shoe soles formed according to the method of this invention.
FIG. 1 shows consecutive steps of a method embodying this invention for making a multi-layer expanded shoe sole that includes an outer sole layer 110 and an inner sole layer 120 surrounded by the outer sole layer 110 (see FIGS. 5 and 6). The method includes the steps of: (a) molding a first foamable material to form a first unexpanded blank 10, and cooling the first unexpanded blank 10 to a low temperature to harden the first unexpanded blank 10; (b) molding a second foamable material to form a second unexpanded blank 20, and maintaining the second unexpanded blank 20 at a high temperature such that the second unexpanded blank 20 is in a softened state; and (c) stacking and thermal molding the first and second unexpanded blanks 10, 20 in a mold 200 (see FIGS. 2 to 4) at a molding temperature to permit the first and second unexpanded blanks 10, 20 to undergo a reaction for cross-linking and expansion and to be formed into the outer and inner sole layers 110, 120, respectively. The mold 200 includes complementary female and male mold halves 210, 220.
The first and second foamable materials are preferably made from a molding composition that contains ethylene-vinyl acetate copolymer (EVA). With EVA as the molding composition, the low temperature for the first unexpanded blank 10 is preferably set in a range of from room temperature to 50° C., the high temperature for the second unexpanded blank 20 is preferably set in a range of from 70 to 110° C., and the molding temperature for the mold 200 is preferably set in a range of from 150 to 180° C.
In this embodiment, the first unexpanded blank 10 has a peripheral wall 11 with a U-shaped cross-section that conforms to an inner wall 212 of the female mold half 210 of the mold 200. The second unexpanded blank 20 has a height greater than and a cross-section smaller than those of a recess 12 defined by the peripheral wall 11 of the first unexpanded blank 10, thus facilitating placement of the second unexpanded blank 20 in the recess 12. The aforesaid cross-section lies in a plane transverse to the height of the second unexpanded blank 20. Since the first unexpanded blank 10 is in a hardened state prior to the reaction, the shape thereof remains substantially the same during the aforesaid reaction, and since the second unexpanded blank 20 is in a softened state prior to the aforesaid reaction, shape of the second unexpanded blank 20 can be made to conform to the shape of the recess 12 in the first unexpanded blank 10 during the reaction, and a clear-cut boundary between the outer and inner sole layers 110, 120 can be achieved, thereby eliminating the aforesaid drawback as encountered in the prior art.
Referring to FIGS. 2 to 4, the first unexpanded blank 10 is formed with a flange 13 that radially and outwardly extends from a top end of the peripheral wall 11 and that is seated on an upper surface 211 of the female mold half 210 adjacent to a groove 213 formed in the upper surface 211 of the female mold half 210 so as to enhance sealing effect between the female and male mold halves 210, 220 during the aforesaid reaction. The flange 13 of the first unexpanded blank 10 results in a flange 130 of the outer sole layer 110 in the groove 213 (see FIGS. 4 and 5). The flange 130 is subsequently trimmed from the outer sole layer 110 to form the final product of the shoe sole of this invention (see FIG. 6).
The male mold half 220 is formed with a groove 223 so as to permit forming of a flange 140 on a top end of the inner sole layer 120.
With the invention thus explained, it is apparent that various modifications and variations can be made without departing from the spirit of the present invention. It is therefore intended that the invention be limited only as recited in the appended claims.
Claims (2)
1. A method for making a multi-layer expanded shoe sole, the method comprising the steps of:
(a) molding a first foamable material to form a first unexpanded blank, and cooling the first unexpanded blank to a low temperature to harden the first unexpanded blank, the first unexpanded blank being formed with a flange extending radially and outwardly from a top end of a peripheral wall of the first unexpanded blank;
(b) molding a second foamable material to form a second unexpanded blank, and maintaining the second unexpanded blank at a high temperature such that the second unexpanded blank is in a softened state; and
(c) stacking and thermal molding the first and second unexpanded blanks in a mold at a molding temperature to permit the first and second unexpanded blanks to undergo a reaction for cross-linking and expansion;
wherein the low temperature is in a range of from room temperature to 50° C., the high temperature is in a range of from 70 to 110° C., and the molding temperature is in a range of from 150 to 180° C.; and
wherein the mold includes complementary male and female mold halves, the flange of the first unexpanded blank being seated on an upper surface of the female mold half so as to enhance a sealing effect between the female and male mold halves during the aforesaid reaction for cross-linking and expansion.
2. The method of claim 1 , wherein the first and second foamable materials are made from a molding composition that contains ethylene-vinyl acetate copolymer.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/213,869 US6787079B2 (en) | 2002-08-05 | 2002-08-05 | Method for making a multi-layer expanded shoe sole |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/213,869 US6787079B2 (en) | 2002-08-05 | 2002-08-05 | Method for making a multi-layer expanded shoe sole |
Publications (2)
Publication Number | Publication Date |
---|---|
US20040021242A1 US20040021242A1 (en) | 2004-02-05 |
US6787079B2 true US6787079B2 (en) | 2004-09-07 |
Family
ID=31187887
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/213,869 Expired - Fee Related US6787079B2 (en) | 2002-08-05 | 2002-08-05 | Method for making a multi-layer expanded shoe sole |
Country Status (1)
Country | Link |
---|---|
US (1) | US6787079B2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040261297A1 (en) * | 2003-06-25 | 2004-12-30 | Park Hyung Jun | Ethylene vinyl acetate based film for crosslinked blown eva foam, shoe components using the same, and method for manufacturing thereof |
US20060192313A1 (en) * | 2005-02-28 | 2006-08-31 | Shen Chiang Y | Method for making a shoe sole component |
WO2015177571A1 (en) | 2014-05-23 | 2015-11-26 | Zotefoams Plc | Method for producing three dimensional foam articles |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7171768B2 (en) * | 2003-10-10 | 2007-02-06 | Skins Footwear, Inc. | Modular shoe system |
US8133420B2 (en) * | 2006-08-09 | 2012-03-13 | Dow Global Technologies Llc | Multi-segment expandable polymer compositions which expand in a controllable direction |
EP2246172A3 (en) * | 2009-03-16 | 2014-06-18 | Lucobit AG | Method for manufacturing light components from foamed plastic |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5141578A (en) * | 1990-11-10 | 1992-08-25 | Yang Kuo Nan | EVA insole manufacturing process |
US5308420A (en) * | 1993-02-22 | 1994-05-03 | Yang Kuo Nan | EVA insole manufacturing process |
US5318645A (en) * | 1993-02-22 | 1994-06-07 | Yang Kuo Nan | EVA insole manufacturing process |
US5972257A (en) * | 1998-09-21 | 1999-10-26 | Liu; Kun-Chung | Process for making a foamed shoe sole |
US6129798A (en) * | 1999-12-14 | 2000-10-10 | Shun-Feng Lu | Process for manufacturing an ethylene vinyl acetate insole |
US6238602B1 (en) * | 1999-12-14 | 2001-05-29 | Kun-Chung Liu | Two-stage forming process for producing an expanded sole |
-
2002
- 2002-08-05 US US10/213,869 patent/US6787079B2/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5141578A (en) * | 1990-11-10 | 1992-08-25 | Yang Kuo Nan | EVA insole manufacturing process |
US5308420A (en) * | 1993-02-22 | 1994-05-03 | Yang Kuo Nan | EVA insole manufacturing process |
US5318645A (en) * | 1993-02-22 | 1994-06-07 | Yang Kuo Nan | EVA insole manufacturing process |
US5972257A (en) * | 1998-09-21 | 1999-10-26 | Liu; Kun-Chung | Process for making a foamed shoe sole |
US6129798A (en) * | 1999-12-14 | 2000-10-10 | Shun-Feng Lu | Process for manufacturing an ethylene vinyl acetate insole |
US6238602B1 (en) * | 1999-12-14 | 2001-05-29 | Kun-Chung Liu | Two-stage forming process for producing an expanded sole |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040261297A1 (en) * | 2003-06-25 | 2004-12-30 | Park Hyung Jun | Ethylene vinyl acetate based film for crosslinked blown eva foam, shoe components using the same, and method for manufacturing thereof |
US7056459B2 (en) * | 2003-06-25 | 2006-06-06 | Hyung Jun Park | Ethylene vinyl acetate based film for crosslinked blown eva foam, shoe components using the same, and method for manufacturing thereof |
US20060192313A1 (en) * | 2005-02-28 | 2006-08-31 | Shen Chiang Y | Method for making a shoe sole component |
WO2015177571A1 (en) | 2014-05-23 | 2015-11-26 | Zotefoams Plc | Method for producing three dimensional foam articles |
US10675792B2 (en) | 2014-05-23 | 2020-06-09 | Zotefoams Plc | Method for producing three dimensional foam articles |
Also Published As
Publication number | Publication date |
---|---|
US20040021242A1 (en) | 2004-02-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN100434258C (en) | Method for flange bonding | |
US6787079B2 (en) | Method for making a multi-layer expanded shoe sole | |
CA2571229A1 (en) | An insulating liner for an article of clothing | |
WO2006076143A3 (en) | Semiconductor die package including universal footprint and method for manufacturing the same | |
JP2018501135A5 (en) | ||
CA2364589A1 (en) | Method for making a shoe | |
CN117584513A (en) | Sole manufacturing method and sole manufactured by same | |
JPS6318097B2 (en) | ||
US20100252962A1 (en) | Molding method and molding apparatus | |
US7076857B2 (en) | Method for making foamed products | |
US8893371B2 (en) | Method of producing a part by decomposition into layers, said part having fluid transfer channels extending through the inter-layers thereof | |
JP2007015152A (en) | Manufacturing method of piece assembling type tire mold | |
JPS6029347B2 (en) | How to manufacture insulation panels | |
US20040021241A1 (en) | Method for making an expanded shoe sole | |
JP5009490B2 (en) | Mold for shoe sole molding | |
US20050273948A1 (en) | Method for making an article of footwear | |
JP3144866U (en) | Mold for manufacturing raw materials | |
KR20170104290A (en) | Vulcanizing mold for tire and tire manufactured by using the same | |
CN2465941Y (en) | High thickness foam shoe sole | |
JPH09206874A (en) | Manufacture of gear | |
TW411262B (en) | Method of producing multi-layered 3-D pattern for shoes | |
JPS6179029A (en) | Method of manufacturing clutch facing | |
JPH03289421A (en) | Manufacturing method of carrier tape | |
EP1473144B1 (en) | Method for making an article of footwear | |
JPH0232054B2 (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: SMALL ENTITY |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20080907 |